题型:选择题 熟石灰可改良酸性土壤,但不能与铵态氮肥混合使用,其原因是两者混合会发生化学反应:Ca(OH)2+2NH4Cl→2X↑+CaCl2+2H2O,则X的化学式为( )A.NH3B.NOC.NO2D.N2 查看答案
题型:选择题 I usually forget the door, but I remembered it when I left yesterday. [ ]A. closing, closingB. to close, to close C. to close, closingD. closing, to close 查看答案